Contact Coagulation Research Articles

Coagulation factor XII genetic variation, ex vivo thrombin generation, and stroke risk in the elderly: results from the Cardiovascular Health Study

The relationships of thrombin generation (TG) with cardiovascular disease risk are underevaluated in population-based cohorts. To evaluate the relationships of TG influenced by the contact and tissue factor coagulation pathways exvivo with common single-nucleotide polymorphisms (SNPs) and incident cardiovascular disease and stroke. We measured peak TG (pTG) in baseline plasma samples of Cardiovascular Health Study participants (n=5411), both with and without inhibitory anti-factorXIa antibody (pTG/FXIa(-) ). We evaluated their associations with ~50000 SNPs by using the IBCv2 genotyping array, and with incident cardiovascular disease and stroke events over a median follow-up of 13.2years. The minor allele for an SNP in the FXII gene (F12), rs1801020, was associated with lower pTG in European-Americans (β=-34.2±3.5nm; P=3.3×10(-22) ; minor allele frequency [MAF]=0.23) and African-Americans (β=-31.1±7.9nm; P=9.0× 10(-5) ; MAF=0.42). Lower FXIa-independent pTG (pTG/FXIa(-) ) was associated with the F12 rs1801020 minor allele, and higher pTG/FXIa(-) was associated with the ABO SNP rs657152 minor allele (β=16.3nm; P=4.3×10(-9) ; MAF=0.37). The risk factor-adjusted ischemic stroke hazard ratios were 1.09 (95% confidence interval CI1.01-1.17; P=0.03) for pTG, 1.06 (95% CI0.98-1.15; P=0.17) for pTG/FXIa(-) , and 1.11 (95% CI1.02-1.21; P=0.02) for FXIa-dependent pTG (pTG/FXIa(+) ), per one standard deviation increment (n=834 ischemic strokes). In a multicohort candidate gene analysis, rs1801020 was not associated with incident ischemic stroke (β=-0.02; standard error=0.08; P=0.81). These results support the importance of contact activation pathway-dependent TG as a risk factor for ischemic stroke, and indicate the importance of F12 SNPs for TG exvivo and invivo.

Competitive sorption of cesium and other microelements onto iron(III) hexacyanoferrate(II) in the presence of humic acids

Experiments show that particles of iron(III) hexacyanoferrate(II) (Berlin Blue, FCFe), in contrast to those of oxyhydrates, and humic acids (HAs) in aqueous solutions have surface charges (ζ-potential) of the same sign. Therefore, contact coagulation and coarsening of FCFe particles in HA solutions are impossible (in contrast, e.g., to dicalcium silicate). HA molecules are capable of dimerization; therefore, the microelements (Cs, Sr, Co, Mn, Fe, Zr, Th, U) in humate solutions form complexes with HA monomer and dimers. It is demonstrated by the example of Cs(I) sorption from humate solutions that the monomeric and dimeric complexes of microelements exhibit different sorption affinity (Kd) for FCFe. Complexes of microelements with HA are kinetically inert and interact with the FCFe sorbent independently of each other. Therefore, it is possible to estimate separately the contribution of each form to the total sorption of the microelement. Except Cs(I), Ce(III), and Th(IV), the microelements under consideration in HA solutions have Kd by orders of magnitude higher than in HA-free solutions. Thus, the FCFe-HA system is capable of binding microelements in the form of humate complexes and of fixing these complexes on the FCFe surface. This phenomenon can be used for efficient decontamination of materials from artificial radionuclides.

Randomized experimental study to investigate the peritoneal adhesion formation of conventional monopolar contact coagulation versus noncontact argon plasma coagulation in a rat model

To investigate peritoneal adhesion formation of monopolar contact coagulation (MCC) versus noncontact argon plasma coagulation (APC) in a rat model. Randomized, controlled, single-blinded animal study. University laboratory. Sixteen female Wistar rats. Bilateral lesions were created on the abdominal wall with MCC and APC in a standard fashion. After 10days, the rats were euthanized to evaluate the peritoneal trauma sites. Adhesion incidence, quantity, and quality were scored 10days postoperatively and studied histopathologically. Average energy intake was 99.5 ± 7.39J for APC and 95.7 ± 9.62J for monopolar contact coagulation. Incidence of adhesion formation was 50.0% for noncontact APC and 85.4% for MCC. MCC induced significantly more vascular adhesions. Histological evaluation revealed no significant differences regarding average depth of lesions induced by APC and MCC. Both groups showed almost identical morphology of necrosis and granulation tissue formation. This study compares for the first time adhesion formation of MCC versus noncontact APC in a rat model. With a similar energy intake, contact coagulation induced a significantly higher rate of adhesion formation. APC-induced adhesions were significantly less vascularized compared with MCC adhesions. Besides the thermal effects of both coagulation methods, the direct mechanical contact of the MCC electrode with the highly sensitive peritoneum is thus determined to be a pivotal additional stimulus for adhesion formation.

Assessing the impact of water treatment on bacterial biofilms in drinking water distribution systems using high-throughput DNA sequencing

Biofilm control in drinking water distribution systems (DWDSs) is crucial, as biofilms are known to reduce flow efficiency, impair taste and quality of drinking water and have been implicated in the transmission of harmful pathogens. Microorganisms within biofilm communities are more resistant to disinfection compared to planktonic microorganisms, making them difficult to manage in DWDSs. This study evaluates the impact of four unique drinking water treatments on biofilm community structure using metagenomic DNA sequencing. Four experimental DWDSs were subjected to the following treatments: (1) conventional coagulation, (2) magnetic ion exchange contact (MIEX) plus conventional coagulation, (3) MIEX plus conventional coagulation plus granular activated carbon, and (4) membrane filtration (MF). Bacterial biofilms located inside the pipes of each system were sampled under sterile conditions both (a) immediately after treatment application (‘inlet’) and (b) at a 1km distance from the treatment application (‘outlet’). Bacterial 16S rRNA gene sequencing revealed that the outlet biofilms were more diverse than those sampled at the inlet for all treatments. The lowest number of unique operational taxonomic units (OTUs) and lowest diversity was observed in the MF inlet. However, the MF system revealed the greatest increase in diversity and OTU count from inlet to outlet. Further, the biofilm communities at the outlet of each system were more similar to one another than to their respective inlet, suggesting that biofilm communities converge towards a common established equilibrium as distance from treatment application increases. Based on the results, MF treatment is most effective at inhibiting biofilm growth, but a highly efficient post-treatment disinfection regime is also critical in order to prevent the high rates of post-treatment regrowth.

Anex vivoevaluation of blood coagulation and thromboresistance of two extracorporeal circuit coatings with reduced and full heparin dose

Bioactive Carmeda® heparin-coated extracorporeal circuits (ECCs) have been shown to reduce contact phase and coagulation activation during cardiopulmonary bypass (CPB). Heparin coating is therefore effective in safely reducing coagulation during routine CPB. Balance® Biosurface is a new, recently developed biopassive coating containing negatively charged sulphonated polymers. This study sought to compare the clotting activation and thromboresistance of the Balance® (B) circuit with that of the Carmeda® (C) with full-dose systemic heparin (FDH) and reduced-dose systemic heparin (RDH). This ex vivo study set-up comprising 40 experiments consisted of simplified ECC and circulation of freshly donated human blood. RDH and FDH regimens were obtained with 0.5 IU/ml and 1 IU/ml heparin administered to reach target activated clotting times (ACTs) of 250 and 500 s, respectively. The study design comprised four groups: FDH-C, FDH-B, RDH-C and RDH-B (all n = 10). Blood was sampled prior to and during the 2-h CPB. Coagulation activation was assessed (FXIIa, F1.2) and electron microscope scan imaging of oxygenators enabled determination of adhesion scores. With a biopassive compared with bioactive surface, mean ACT was lower, regardless of the heparin regimen applied (P < 0.001), whereas the total heparin dose required to maintain ACT was above target level (P < 0.001). However, FXIIa and F1.2 values were similar in all groups throughout, as were pressure gradients among oxygenators. All groups demonstrated similar adhesion scores following ultrastructural oxygenator assessment. In the absence of surgical-related haemostatic disturbances and based on target ACT levels under reduced- or full-dose heparin, the clotting process was similar to heparin-coated and new sulphonated polymer-coated ECC, both demonstrating similar thromboresistance.

PHYSICO-CHEMICAL THEORY OF THE COAGULATION WATER TREATMENT. THE INFLUENCE OF VARIOUS FACTORS ON THE PROCESS (REPORT 2)

From the standpoint of a new physical-chemical water treatment coagulation theory, proposed by the author, the theoretical basis of the hydrolysis of coagulants and coagulation process of pollutants of natural waters to produce potable water condition.The influence of temperature, pH, ionic composition, mixing, additives and opacifiers flocculants on the process of coagulation. Analyzed the different ways of feeding coagulants to purify water. Particular attention is paid to the contact coagulation, which allows to intensify the process of drinking water, reducing reagent consumption and improve the quality of treated water.

Influence of single nucleotide polymorphisms in factor VIII and von Willebrand factor genes on plasma factor VIII activity: the ARIC Study

AbstractFactor VIII (FVIII) functions as a cofactor for factor IXa in the contact coagulation pathway and circulates in a protective complex with von Willebrand factor (VWF). Plasma FVIII activity is strongly influenced by environmental and genetic factors through VWF-dependent and -independent mechanisms. Single nucleotide polymorphisms (SNPs) of the coding and promoter sequence in the FVIII gene have been extensively studied for effects on FVIII synthesis, secretion, and activity, but impacts of non–disease-causing intronic SNPs remain largely unknown. We analyzed FVIII SNPs and FVIII activity in 10 434 healthy Americans of European (EA) or African (AA) descent in the Atherosclerosis Risk in Communities (ARIC) study. Among covariates, age, race, diabetes, and ABO contributed 2.2%, 3.5%, 4%, and 10.7% to FVIII intersubject variation, respectively. Four intronic FVIII SNPs associated with FVIII activity and 8 with FVIII-VWF ratio in a sex- and race-dependent manner. The FVIII haplotypes AT and GCTTTT also associated with FVIII activity. Seven VWF SNPs were associated with FVIII activity in EA subjects, but no FVIII SNPs were associated with VWF Ag. These data demonstrate that intronic SNPs could directly or indirectly influence intersubject variation of FVIII activity. Further investigation may reveal novel mechanisms of regulating FVIII expression and activity.

Coagulation's Contact Activation System Again Stands Accused

Coagulation's Contact Activation System Again Stands Accused

A phase 2 prospective, randomized, double-blind trial comparing the effects of tranexamic acid with ecallantide on blood loss from high-risk cardiac surgery with cardiopulmonary bypass (CONSERV-2 Trial)

Ecallantide is a recombinant peptide in the same class as aprotinin that inhibits plasma kallikrein, a major component of the contact coagulation and inflammatory cascades. Therefore, ecallantide was expected to reduce blood loss associated with cardiac surgery requiring cardiopulmonary bypass. This prospective multinational, randomized, double-blind trial enrolled patients undergoing cardiac surgery using cardiopulmonary bypass for procedures associated with a high risk of bleeding. Patients were randomly assigned to ecallantide (n = 109) or tranexamic acid (high dose, n = 24; low dose, n = 85). Efficacy was assessed from the volume of packed red blood cells administered within the first 12 hours after surgery. The study was terminated early after the independent data safety and monitoring board observed a statistically significantly higher 30-day mortality in the ecallantide group (12%) than in the tranexamic acid groups (4%, P = .041). Patients receiving ecallantide received more packed red blood cells within 12 hours of surgery than tranexamic acid-treated patients: median = 900 mL (95% confidence interval, 600-1070) versus 300 mL (95% confidence interval, 0-523) (P < .001). Similar differences were seen at 24 hours and at discharge. Patients treated with the higher tranexamic acid dose received less packed red blood cells, 0 mL (95% confidence interval, 280-600), than the group treated with the lower dose, 400 mL (95% confidence interval, 0-400) (P = .008). No deaths occurred in the higher dose tranexamic acid group. Ecallantide was less effective at reducing perioperative blood loss than tranexamic acid. High-dose tranexamic acid was more effective than the low dose in reducing blood loss.

Properties of anion exchange resins exhausted by humic compounds

The loading of anion exchange resins with humic compounds adsorbed during industrial water treatment processes has been investigated. It has been found that humic compounds are uniformly distributed throughout the bead. Fresh and exhausted anion exchange resins have been studied with respect to their ability to be loaded with Fe(III) oxides. The results show that anion exchangers containing humic compounds retain iron better than fresh ones. The uptake may be due to catalytic oxidation and contact coagulation at the surface.

The Tick Protein Ir-Cpi Efficiently Delays Contact Pathway Induced Thrombin Generation and Displays In Vivo Antithrombotic Activity

AbstractAbstract 3336 Introduction:The search for new anticoagulants is a major challenge in medicine. Contact factors have never been considered as interesting targets for the development of new anticoagulant agents since they are not required for in vivo coagulation (i.e. deficiencies affecting these factors do not cause excessive bleeding). The discovery that FXI and FXII deficiency protects against thrombosis without causing spontaneous bleeding in mice makes FXII a unique and ideal target for drug design. We demonstrated in vitro that Ir-CPI, a 67 amino acids recombinant Kunitz-type protein from Ixodes ricinus, specifically interacted with activated human contact phase factors (FXIIa, FXIa, and kallikrein). Aims:The goal of this study was to investigate the potential anticoagulant and antithrombotic efficacy of Ir-CPI. Methods:The effects of Ir-CPI were investigated on the thrombin activity during the coagulation process in human plasma using the CAT method. Three different inducers were employed to specifically trigger the coagulation pathways and to generate thrombin. A standard concentration of 5 pM TF with 4 μM PL and 16.7 mM CaCl2 was used to activate the TF pathway whereas a lower TF concentration of 1 pM with 4 μM PL and 16.7 mM CaCl2 was selected for stimulating the TF pathway in combination with the contact phase pathway through a thrombin-mediated positive feedback. The contact phase pathway was also triggered alone by ellagic acid, PL and 16.7 mM CaCl2 (25-fold diluted APTT reagent Actin FS). The effect of Ir-CPI on venous thrombus formation was assessed using a rat thrombosis model induced by complete venous stasis in the posterior vena cava and FeCl3 topical application on the outer vessel wall. Results:When stimulating plasma coagulation trough the contact pathway, Ir-CPI caused a concentration-dependent prolongation of the lag time and the Tmax and a concentration-dependent decrease in the Cmax compared to the control curve (i.e. without inhibitor). When the coagulation cascade was triggered by the TF pathway (5 or 1 pM TF), only a slight concentration-dependent decrease of the Cmax and a concentration-dependent prolongation of the lag time and the Tmax were observed. For comparison purpose, the effects of the specific competitive FXIIa inhibitor corn trypsin inhibitor (CTI) were also investigated using the three same inducers than for Ir-CPI. For the contact pathway, a concentration-dependent decrease of the Cmax and a concentration-dependent prolongation of the lag time and the Tmax were found. When stimulating the TF pathway (5 or 1 pM TF), no modification of the thrombin generation curves was observed with the tested concentrations of CTI. When comparing the results of the two inhibitors acting trough the delay of the contact pathway, we found that Ir-CPI was about 30-fold more potent than CTI.We further evaluated the antithrombotic effect of Ir-CPI on a rat venous thrombosis model induced by endothelial damage and vessel ligation, close to the physiological venous thrombus formation in humans. We showed that Ir-CPI reduced thrombosis in a dose-dependent manner with an ED50 close to 65 μg/kg. A maximum effect starting from 0.5 mg/kg was observed with a mean reduction in the clot weight/body weight of 75 ± 7%. This antithrombotic effect of Ir-CPI was exclusively mediated through the inhibition of thrombin generation since it did not interference with collagen-induced platelet aggregation. This is the first time that an inhibitor of the coagulation contact phase was shown to protect against the formation of venous thrombi. The antithrombotic effect of Ir-CPI was also confirmed using other venous and arterial thrombosis models. We also showed that the effective antithrombotic dose of Ir-CPI in these tests did not promote bleeding or impair blood coagulation parameters. Conclusions:The present study demonstrated that Ir-CPI, a recombinant protein from the tick Ixodes ricinus targeting the contact factors (FXII, FXI and kallikrein), displayed an anticoagulant activity mainly through the delay of the contact pathway induced thrombin generation. This drug also exhibited an antithrombotic activity in our venous and arterial thrombosis model. This drug may thus provide an interesting and innovative therapeutic tool for the prevention and the treatment of thromboembolic diseases with a minimal risk of therapy-associated bleeding. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Оценка эффективности коагулянтов и флокулянтов при осветлении поверхностных вод

A comparative assessment of different agents for treatment of surface waters in the process of volume and contact coagulation has been performed. The volume coagulation at the “Mayak” filtering station, the town of Polevskoy, proved aluminum sulfate and aluminum-iron coagulant the most effective for water treatment during the flood period. To attain norm indicators of the purified water it is necessary to use flocculants and auxiliary agents. It is a good practice to use flocculating mixtures for contact coagulation.

Ir-CPI, a coagulation contact phase inhibitor from the tick Ixodes ricinus, inhibits thrombus formation without impairing hemostasis

Blood coagulation starts immediately after damage to the vascular endothelium. This system is essential for minimizing blood loss from an injured blood vessel but also contributes to vascular thrombosis. Although it has long been thought that the intrinsic coagulation pathway is not important for clotting in vivo, recent data obtained with genetically altered mice indicate that contact phase proteins seem to be essential for thrombus formation. We show that recombinant Ixodes ricinus contact phase inhibitor (Ir-CPI), a Kunitz-type protein expressed by the salivary glands of the tick Ixodes ricinus, specifically interacts with activated human contact phase factors (FXIIa, FXIa, and kallikrein) and prolongs the activated partial thromboplastin time (aPTT) in vitro. The effects of Ir-CPI were also examined in vivo using both venous and arterial thrombosis models. Intravenous administration of Ir-CPI in rats and mice caused a dose-dependent reduction in venous thrombus formation and revealed a defect in the formation of arterial occlusive thrombi. Moreover, mice injected with Ir-CPI are protected against collagen- and epinephrine-induced thromboembolism. Remarkably, the effective antithrombotic dose of Ir-CPI did not promote bleeding or impair blood coagulation parameters. To conclude, our results show that a contact phase inhibitor is an effective and safe antithrombotic agent in vivo.

Activation of the contact system and inflammation after thrombolytic therapy in patients with acute myocardial infarction

Thrombolytic therapy activates the contact system, and factor XII activation may activate the coagulation cascade and inflammation. It is not known whether an early inflammatory response is induced by thrombolytic therapy in patients with acute myocardial infarction (AMI). We prospectively measured the plasma levels of activated factor XII, cleaved kininogen, prothrombin fragment 1 + 2 (as indexes of the contact phase and coagulation activation), and interleukin-6 and C-reactive protein (CRP) (as indexes of inflammation) in 39 patients hospitalized for AMI within 12 hours of symptom onset: 26 receiving thrombolytic therapy and 13 heparin alone. Blood samples were collected at baseline and after 90 minutes and 24 hours. Patients undergoing thrombolysis had a significant early increase in activated factor XII (from 2.2 ng/ml at baseline to 4.7 ng/ml after 90 minutes; p = 0.0001), cleaved kininogen (from 26% to 37%; p = 0.001), and fragment 1 + 2 (from 1.4 to 2.1 nmol/L; p = 0.0001), whereas the 24-hour levels were similar to baseline levels. The levels of interleukin-6 significantly increased during the first 90 minutes (from 3.9 to 6.3 μg/ml; p = 0.001), and were even higher after 24 hours (11.9 ng/ml, p = 0.0001). CRP levels increased only after 24 hours (p = 0.0001). There were no changes in these parameters in patients receiving heparin alone, except for a 24-hour increase in interleukin-6 and CRP levels. Thus, in patients with AMI receiving thrombolytic therapy, early activation of inflammation parallels the activation of the contact system and the coagulation cascade, which might contribute to microvascular obstruction and reperfusion injury.

Surface interactions of oxidized cellulose with fibrin(ogen) and blood platelets

Hemostatic effects of oxidized cellulose are well known but the mechanism of its action is far from being well understood. Hemostatic (hemostyptic) biomaterials with their ability to initiate or accelerate thrombus formation belong to surgical sealants. Thrombus formation is a surface phenomenon. The exploitation of surface plasmon resonance sensing principle for the examination of interactions of oxidized cellulose with fibrinogen, fibrin and blood platelets is reported. Cellulose decreased and slowed down the interaction of immobilized fibrin monomer with fibrinogen as observed by surface plasmon resonance. Only weak interactions of cellulose with plasma proteins albumin and fibrinogen were observed. Delayed gelation and slower increase in turbidity occurred in fibrinogen–thrombin solutions in the presence of the cellulose. Platelets in plasma but not washed platelets in a buffer were activated in the presence of cellulose. We suppose that activation of the coagulation contact system of blood plasma initiated very likely by the negatively charged surface of the oxidized cellulose leads to the fibrin formation and activation and adhesion of blood platelets. The direct interactions of platelets and fibrinogen with the cellulose seem to play a secondary role.

Sewing machine and experimental devices for nonvariceal hemorrhage

Current endoscopic methods for hemostasis in the gastrointestinal tract, such as injection, thermal probes, and lasers, are relatively ineffective if a large artery is eroded by an ulcerating process. This article will review some experimental endoscopic devices that have been developed to treat bleeding from bleeding peptic ulcer and other sources of gastrointestinal bleeding. Progress with methods for flexible endoscopic suturing using sewing machines is reviewed and methods for tying knots and cutting thread are described. Other mechanical methods of endoscopic ulcer hemostasis are reviewed, including stapling, the application of clips, elastic bands, ulcer clamps, endoloops, screws, balloon, and ferromagnetic tamponade. Some less commonly used thermal methods are also described, including microwave and argon plasma coagulation, bipolar forceps, sapphire, and polytetrafluoroethylene-tipped contact laser probes. The advent of new endoluminal surgical methods such as transgastric surgical techniques using rigid laparoscopic instruments and flexible endoscopic ulcer excision with wound closure are described.

Thermodynamic instability of disperse media isolated from external actions

The evolution of the structure of a medium containing disperse elements (the drops in a weakly viscous fluid, rigid spheres in glycerin, and air pores in a gel) is studied experimentally in the case where the gradient temperature and the concentration fields are absent in the system, and the medium is isolated from the influence of an external force field (including gravity forces). It is shown that these systems are nonequilibrium: if the initial distance between disperse particles is of the order of their sizes, the particles approach until they come in contact (coagulation) irrespective of the scale of the system.

Plasma proteolytic activity in liver transplant rejection.

In this study, we evaluated the role of proteolytic enzymes belonging to the coagulation, fibrinolytic, and plasma contact systems in the early postoperative phase after orthotopic liver transplantation (OLT). Twenty-nine patients were studied at the time of OLT and during the first 2 postoperative weeks. Blood samples were collected daily after OLT and analyzed for kallikrein-like activity (KK), functional kallikrein inhibition (KKI), plasmin-like activity (PL), and alpha2-antiplasmin (AP). In addition, prekallikrein (PKK), prothrombin (PTH), antithrombin III (AT III), plasminogen (PLG), prothrombin/antithrombin III complexes (TAT), prothrombin fragment 1 + 2 (F1 + 2), and plasmin/alpha2-antiplasmin complexes (PAP) were measured. Nineteen patients experienced biopsy-verified acute rejections (AR) and ten patients had uneventful courses and served as controls. Plasma analyses showed that the contact, coagulation, and fibrinolytic systems were activated during OLT. Following OLT, continuous thrombin and plasmin generation was observed, and these effects were more pronounced in the group having an uneventful course than in patients with AR. Factors that could possibly affect plasma proteolytic activity, such as blood product usage during and after OLT and cold ischemia time of the liver graft, did not differ between the groups, nor did the routine liver function tests, alanine aminotransferase (ALT) and aspartate aminotransferase (AST).

Operative results after primary and secondary debulking-operations in advanced ovarian cancer (AOC).

To assess the role of primary and secondary radical surgery in advanced ovarian cancer (AOC). Retrospective study. One hundred and fifty-one patients with AOC (FIGO III/IV) underwent altogether 191 extended multivisceral operations between 1/1992 and 2/1998. The statistic analysis compared the primary with the secondary operations. One hundred and seventeen patients had a primary, 63 patients had a secondary and 18 patients a tertiary operation because of relapse of ovarian cancer. Surgical procedures entailed respectively: small-bowel-resection (21%/48%), colon resection (39%/58%), colostomy (9%/11%), ileostomy (2%/4%), ileum-pouch (0%/6), splenectomy (3%/3%), pelvic floor-covering (4%/6%), peritoneal removal (24%/21%), infrared contact coagulation (4%/6%). Seventy-five percent of the patients had no complications: relaparotomy (3%/3%), fistula (3%/6%), short-bowel-syndrome (5%/11%), postoperatively mortality (2%/6%). Postoperative tumor-free were 26%/22%, 57% and 65% had residual disease < or = 2 cm, 16%/13% > 2 cm. Radical multivisceral surgery is feasible, safe and efficient in primary as well in secondary situation of advanced ovarian cancer.

Preozonation coupled with flotation filtration: successful removal of algae

The renovating of a new water treatment plant in Paris which produces 15% of the capital's drinking water supply is described: an original treatment plant consisting of a preozonation, a flotation with a low level of coagulant coupled with contact coagulation. Coagulation on filter has been tested on a pilot plant. The results are excellent (95 to 99%) and have led to the building of a new water treatment plant with very flexible operating conditions depending on the quality of the water.